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Windows 7: cant start defender cant install MSE error code:0x8004FF91

Running your computer without an AV program is not good. It is like throwing a magnet in a bucket of nails.

For now, you may want to consider installing Panda Free AntiVirus. It is light on resources.
I have it installed, and have no problems. You do, on occasion, get a pop-up asking if you want to upgrade to the paid version. I always decline.

Running your computer without an AV program is not good. It is like throwing a magnet in a bucket of nails.

For now, you may want to consider installing Panda Free AntiVirus. It is light on resources.
I have it installed, and have no problems. You do, on occasion, get a pop-up asking if you want to upgrade to the paid version. I always decline.

Running your computer without an AV program is not good. It is like throwing a magnet in a bucket of nails.

For now, you may want to consider installing Panda Free AntiVirus. It is light on resources.
I have it installed, and have no problems. You do, on occasion, get a pop-up asking if you want to upgrade to the paid version. I always decline.

There are no issues reported with Windows Defender or Microsoft Security Essentials.

Will take a look at the reports once again, and prepare a script to remove some items. However, even doing this may not open the door for WD and MSE to work on this machine. There may be Registry entries or some file that still remains in the system. These issues are very difficult to resolve.

Please open Notepad (Start > All Programs > Accessories > Notepad)
Copy the entire contents of the code box below (Do not copy the word 'code') to Notepad.
Save it to the Desktop, and name it: fixlist.txt

Win 7 Ultimate, clean install, get 0x8004FF91 trying to install MSEThis machine is a Gateway FX-Series laptop, which I bought used a couple of months ago. It came without a drive, so I bought a new 2TB drive to go along with it. I installed Win 7 Ultimate onto it and just a small handful of other programs so far -- a couple of browsers and utilities for my digital...

Windows Updates & Activation

error code 0x8004FF91 when I try to start MSEI wonder if I might could just step in here rather than start a new thread. I'm having the same problem Foxen did. I get the error code 0x8004FF91 when I try to start MSE.
Okay, here's a bit about my situation. This is a notebook with a clean 2 TB hard drive onto which I installed Win7 Ultimate....

System Security

Windows Defender error code Ox80070424In attempting to fix my email display, I discovered Windows Defender is not turned on, and cannot be turned on. I have looked for MSE in my Programs list and don't see it. In addition, when I click on Windows Defender in the Control Panel, it shows its last scan December 12, 2011- 1 year ago.
I...